title: Evaluation of 18F-FDG excretion patterns in malignant obstructive uropathy.
abstract: OBJECTIVE
  This study aims to evaluate whether (18)F-FDG excretion patterns reflect renal function in malignant obstructive uropathy and to evaluate if these patterns predict internal ureteral stent success.
  
  
  METHODS
  One hundred twelve patients who underwent PET/CT for abdominal tumors and displayed hydronephrosis on CT and 59 patients who underwent PET/CT for cancer screening were included in a retrospective study. Hydronephrosis was graded by initial CT and correlated with visual analysis of (18)F-FDG renal parenchymal uptake and excretion patterns. Stent insertion was performed for 84 patients after PET. Follow-up CT was reviewed for hydronephrosis improvement.
  
  
  RESULTS
  There were 4 PET patterns in obstructive hydronephrosis which correlated linearly with hydronephrosis severity and serum creatinine levels. Patients with no parenchymal retention and renal excretion (PET pattern 1) showed 97% (28/29) hydronephrosis improvement after stent insertion, and patients with no parenchymal retention and no renal excretion showed 0% (0/9) hydronephrosis improvement after stent insertion. Multivariate analysis showed creatinine levels and PET pattern predicted stent success, but CT hydronephrosis did not.
  
  
  CONCLUSIONS
  There are 4 PET patterns of obstructive hydronephrosis which correlated with hydronephrosis grade and creatinine levels. Some of these PET patterns can be useful in the prediction of hydronephrosis improvement after stent insertion. Recognition of these patterns in obstructive hydronephrosis may be helpful in improving patient prognosis and quality of life.
authors.affiliation: Departments of Nuclear Medicine, Yonsei University Health System, Seoul, Korea.
authors.forename: Arthur
authors.initials: A
authors.lastname: Cho
authors.forename: Yong Eun
authors.initials: YE
authors.lastname: Chung
authors.forename: Jae-hoon
authors.initials: JH
authors.lastname: Lee
authors.forename: Mijin
authors.initials: M
authors.lastname: Yun
authors.forename: Jong Doo
authors.initials: JD
authors.lastname: Lee
authors.forename: Won Jun
authors.initials: WJ
authors.lastname: Kang
mesh_terms: D003710:Demography; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D006869:Hydronephrosis / Q000000981:diagnostic imaging*; D007668:Kidney / Q000000981:diagnostic imaging*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography; D015607:Stents; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
chemical_list: D019788:Fluorodeoxyglucose F18